The present invention relates to a self-propelled agricultural harvesting machine that includes an installed front attachment which is supported when in a non-working position by at least one support wheel system which is in contact with the ground, and that includes a braking device.
The output of agricultural harvesting machines continues to increase, thereby requiring the use of increasingly larger and heavier front attachments. Typically, headers of combine harvesters are detached from the combine harvester and placed on a carriage in order to be hauled on the road. In contrast, corn headers and corn pickers are typically not detached from forage harvesters in preparation for travel on the road; instead, they remain attached to the forage harvester. In preparation for travel on the road, these front attachments can be folded using different types of folding mechanisms, in order to decrease their width, as is the case with grain-cutting devices.
A disadvantage of this is the fact that, since the front attachment is situated on the carriage and the weight is therefore shifted onto the individual axles, in particular due to the reduction of the load on the front braked drive axle, the harvesting machine requires a longer braking distance once braking is activated, with the result that limits in terms of a maximum permissible braking distance are exceeded. There is also the problem that, when the load on the front braked drive axle is too great, the rear of the harvesting machine is lifted off of the ground during braking.
DE 199 18 551 makes known an agricultural harvesting machine designed as a forage harvester that includes an intermediate attachment on the front side that accommodates an agricultural working device. To ensure that the load of the agricultural working device need not be supported exclusively by the carrier vehicle axle situated at the front relative to the direction of travel, it is provided in at least one embodiment that support wheels are assigned to the intermediate attachment that make it possible for at least a portion of the mass of the agricultural working device to be supported on the ground via these support wheels so that, provided that the support wheel is in contact with the ground, a distribution of axle load is attained that fulfills the applicable requirements. The disadvantage of this, however, is that, given that the available support wheel absorbs a partial load of the installed front attachment, the resultant distribution of axle load negatively affects the braking procedure in that the axle load on the braked drive axle is no longer sufficient, with the result that limits in terms of a permissible maximum braking distance may be exceeded.
Publication DE 10 2005 001 412 A makes known a carriage which is used to support a front harvesting attachment which is installed on a harvesting machine. To relieve weight from the wheels of the harvesting machine, the carriage includes at least one wheel that extends downward and that is installed on the carriage frame using a resilient element. Spring action is attained using a hydraulic cylinder which is connected to a pressure reservoir and forms a closed system which may be separated from the hydraulic system of the harvesting machine for travel on the road. The pressure is adjusted in such a manner that a desired drivability of the carriage may be attained.